Expression of transforming growth factor-beta 1 in rat embryohic cochlea / 中国组织工程研究

ABSTRACT

BACKGROUND:Many researches on the development of cochlea have been made, but mainly depend on the pathological conditions and developmental deformity, while the researches on the development process of normal embryonic cochlea and expression of related factors are rare. OBJECTIVE:To investigate the expression of transforming growth factorβ1 in rat embryonic cochlea. METHODS:Fifty-six Sprague Dawley rats were selected and the rats were pregnancy, and the embryos were obtained from the rats, trimmed the inner ear specimens under the anatomical microscope, and then the specimens were treated with dehydration, decalcification, directly paraffin embedding and slicing processing. The morphology evolution of inner cochlea was observed under light microscope after hematoxylin-eosin staining. The expression of transforming growth factorβ1 in rat embryonic cochlea was observed by immunohistochemical streptavidin biotin-peroxidase complex method. RESULTS AND CONCLUSION:The development of rat inner ear began in ectoderm thickening area of E8 phase, otocyst and the emergency of the mesenchymal could be seen in E9 phase, otocyst and ossicular chain began to develop in E9.5 phase, formation of cochlear duct anlage could be seen in E12.5 phase, cochlea tube development was completed in E18.5 phase and Corti’s formation could be seen in E16 phase. The structure and function of the inner ear could be ful y developed after birth. The expression of transforming growth factorβ1 could be seen in E12.5-E19 phases, and the expression was changed from weak to strong and then weakened further, and strongest in E14.5 phase. This suggested that transforming growth factorβ1 may be involved during the development of rat cochlear epithelium.